1. Field of the Invention
The present invention relates to motor vehicles in general, and more particularly to arrangements for visualizing the areas illuminated by the vehicle headlights as the vehicle travels on a road.
2. Description of the Related Art
There are already known various constructions of arrangements for visualizing, under simulated conditions, the areas that are illuminated by vehicle headlights as the vehicle travels in the forward direction.
One such arrangement is disclosed in German published patent application DE 38 26 813 A1. In this arrangement, an actual scene is captured by a camera as it is being illuminated by an actual headlight. The illumination of the area in front of the vehicle can be examined during the rendition of the captured scene on a rendering device. During the rendition, the illumination provided by the real headlight can be altered in a location-dependent manner, in order to be able to test a different headlight that emits a light beam possessing characteristic properties different from those of the original light beam. A particular drawback of this approach is, however, that the underlying illumination by the actual headlight forms the basis for the rendition, so that it is not possible to examine the illumination occurring while the vehicle is being driven under different operating conditions of the vehicle and/or under changing environmental conditions.
Accordingly, it is a general object of the present invention to avoid the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a headlight illumination visualization arrangement that does not possess the drawbacks of the known arrangements of this type.
Still another object of the present invention is to devise an arrangement of the type here under consideration that would make it possible to examine the illumination under a variety of conditions.
It is yet another object of the present invention to design the above arrangement in such a manner as to be able to take into account the dynamically changing operational and environmental conditions as they influence the headlight illumination, without having to actually drive the vehicle under all such conditions.
A concomitant object of the present invention is so to construct the arrangement of the above type as to be relatively simple in construction, inexpensive to manufacture, easy to use, and yet reliable in operation.
In keeping with the above objects and others which will become apparent hereafter, one feature of the present invention resides in n arrangement for visualizing the illumination by at least one vehicle headlight of a zone situated in front of the vehicle as considered in the forward driving direction. This arrangement includes a camera mounted on the vehicle and operative for taking a succession of scenes of the environment of the vehicle including the aforementioned zone as the vehicle travels on a roadway in the forward driving direction; means including a monitor for visually rendering the scenes obtained from the camera; and means for presenting a simulated rendition of the region illuminated by the headlight in the succession of scenes appearing on the visually rendering means. A particular advantage of the arrangement as described so far is that it enables the person using the same to examine the illumination of the zone ahead of the vehicle by the headlight or headlights under changing conditions without actually having to drive the vehicle under such conditions and having to observe the illumination at the same time.
Advantageously, the arrangement as defined further includes means for capturing the position of the camera with respect to the roadway for each of the scenes in the succession. The capturing means advantageously includes at least one sensor device for capturing the position of the camera during the vehicle travel. These features facilitate the association of the respective illuminated area with the roadway.
According to another advantageous aspect of the present invention, the presenting means includes means for presenting the roadway in front of the vehicle and/or means for presenting respective edges of the roadway in front of the vehicle in an especially emphasized manner. This makes it possible to easily determine and present the illuminated area in the rendition.
It is further advantageous for the presenting means to include means for presenting respective making lines in the scenes representative of distances in at least one of the direction of travel of the vehicle and transversely thereto. This makes it relatively easy to determine the distance of the illuminated area either in front of the vehicle or in the lateral direction from the longitudinal axis of the vehicle from its simulation on the monitor. The device may further include means for indicating the instantaneous direction of travel of the vehicle.
It is also of advantage when the visually rendering means is operative for simulating the roadway as a plane, and when the presenting means includes means for simulating the light beam issued by the headlight as a light cone, and for presenting the area of intersection of the thus simulated light cone with the simulated plane of the roadway in front of the vehicle in an especially emphasized manner. Generally speaking, though, it is advantageous for the presenting means to include means for simulating the light beam issued by the headlight in a simplification as a light cone. In this context, it is also advantageous when the presenting means present respective edges of an area of intersection of the thus simulated light cone with the roadway in front of the vehicle in an especially emphasized manner. Similarly, it is advantageous when the presenting means includes means for presenting the center point of an area of intersection of the thus simulated light cone with the roadway in front of the vehicle in an especially emphasized manner.
According to another facet of the present invention, there is provided means on the vehicle for influencing at least one characteristic property of the light beam issued by the headlight in dependence on at least one of an operating parameter of the vehicle and an environmental condition. Such influencing means may advantageously include at least one sensing device for detecting the at least one of an operating parameter of the vehicle and an environmental condition. Last but not least, the sensing device is operative for sensing the inclination of the vehicle with respect to the roadway, and the influencing means is operative for adjusting the direction in which the headlight issues its light beam in such a manner in dependence on the inclination of the vehicle as determined by the sensing device that the distance at which the light beam is aimed in front of the vehicle remains at least substantially constant. These features facilitate the examination of the illuminating performance of the headlights of different configurations and under varying conditions, with a view toward implementing the thus gathered knowledge in the actual vehicles and/or their headlight systems.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.